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Particulate Radiation

There are three types of Particulate Radiation and they are of little concern to the average radiographer.

Particulate Radiation is different from X and Gamma Rays they have mass and do not travel at the speed of light.

However, Particulate Radiation will penetrate matter, will case ionization and cannot be detected by human senses. 1.Alpha Radiation as discussed in Lesson 4 has a positive charge and is slow and heavy.

       Alpha Particles ionize atoms by removing electrons as they pass but they do not penetrate deeply. 2.Beta Particles (High Speed Electrons) have a negative charge and because they are lightweight, they are not as ionizing alpha particles. 3.Neutron Radiation has peculiar penetrating qualities. It penetrates many heavy elements with ease and is absorbed readily by many lighter elements, particularly Hydrogen.

       This quality is just the reverse of  X and Gamma Rays.

       The Neutron Source is usually collimated and passes through the specimen to activate a conversion screen.

       When the activated conversion screen is exposed to X-Ray Film or some other image recorder, the image is transferred

       by the ionizing radiation from the conversion screen. 

Working Gamma Source:
A “drive cable” is connected to the other end of the camera. This cable, controlled by the radiographer, is used to force the radioactive material out into the guide tube where the gamma rays will pass through the specimen and expose the recording device.

Sources Of Radiation:
An Electron volt is an amount of energy equal to the energy. Gained by one electron when it is accelerated by one volt.
If one electron were accelerated by a potential of 100 Thousand volt ( 100 KV ). X-ray machine, The electron would have an energy of 100 thousand electrons volt/ 100 KeV.
When X- rays are produced, there is a wide range of energies ( wave Length ) Not all electrons are accelerated to the maximum voltage set on the X-ray machine.
However every gamma producing isotope emits rays of one or more specific energies.
Regardless of curies strength (Activity) or size of an isotope. The energy of individual rays remains the same

Sources of Radiation:
X-ray and gamma rays are not bits of matter as are alpha and beta particles. X- ray and gamma have no mass or weight and our normal senses can not detect them. The energy of X- ray and Gamma Rays is measured in :
Thousand electron volt ( KEV )
Million Electron Volt ( Mev )
An Electron volt is an amount of energy equal to the energy. Gained by one electron when it is accelerated by one volt.
If one electron were accelerated by a potential of 100 Thousand volt ( 100 KV ). X-ray machine, The electron would have an energy of 100 thousand electrons volt/ 100 KeV.
When X- rays are produced, there is a wide range of energies ( wave Length ) Not all electrons are accelerated to the maximum voltage set on the X-ray machine.
However every gamma producing isotope emits rays of one or more specific energies.
Regardless of curies strength (Activity) or size of an isotope. The energy of individual rays remains the same

Generation of Gamma Waves:

Unlike X-rays, which are produced by a machine, gamma rays cannot be turned off. Radioisotopes used for gamma radiography are encapsulated to prevent leakage of the material.

Measurement Of Radioactivity:
The basic unit of radioactive material is the “ curie”. When a radioactive material decays it is said to have an “activity” of one curie when 37 billion of its atoms disintegrate in one second.

Radioactive Material:: No two radioactive isotopes have exactly the same decay pattern a radioactive isotopes can decay by any of the following:

1.Alpha Emission only.

2.Beta Emission only.

3.Alpha emission with associated gamma rays emission. 4.Beta emission with associated gamma ray emission.